Twenty years into her marriage, Kat and her husband faced head-on the
great underlying fear of most monogamous people: My partner wants to
have sex with other people. For them, that truth led to a rollercoaster
of new sexual and romantic adventures...

It has a significant narrowing in the neck, which allows it to stay in place much better than many (I still shot it out when I came hard enough, but I don't know any plug I haven't launched while squirting).